3249: Neutrino Project

2026-05-29T07:10:38Z

2001:8004:20B0:E688:879:CB84:7F7D:100: erroneous comma

{{comic
| number = 3249
| date = May 22, 2026
| title = Neutrino Project
| image = neutrino_project_2x.png
| imagesize = 324x471px
| noexpand = true
| titletext = We definitely put the pool in a mine for shielding. It was absolutely not to hide it from the funding people.
}}

==Explanation==
{{incomplete|This page was created recently by a solar neutrino. Don't remove this notice too soon. In particular, the statement comparing the cost of a pool with the cost of a detector needs to be substantiated or removed.}}

A {{w|neutrino}} is a type of subatomic particle that interacts extremely rarely with matter. In nearly all cases, neutrinos pass through objects, regardless of density or composition, with no effects whatsoever unless there are {{What If|73|a lot of them}}. For instance, about [https://icecube.wisc.edu/news/press-releases/2017/11/first-look-at-how-earth-stops-high-energy-neutrinos-in-their-tracks/ 100 trillion neutrinos pass through your body every second] to no noticeable effect.

However, there is a very small chance that a neutrino will collide with any material, including water, which has the advantage of being transparent to the light that occurs due to {{w|photon}}s being produced by that interaction. Neutrinos can thus be detected by constructing a large pool of water, shielded from as many other particles and radiations as possible, and carefully monitoring it for the small flashes of light that occur when a neutrino does interact with one of the many water molecules within the pool. {{w|Photomultiplier tubes}} are used to assist in detecting these very faint and infrequent flashes and reveal the possible nature (and direction) of the interactions that caused them.

The comic jokes that these detectors were not constructed with this purpose in mind. Instead, [[Cueball]] and [[Ponytail]], the organizers of this project, obtained funding for a "neutrino project" and then embezzled these funds for a {{w|Party#Pool_party|pool party}}, likely primarily to buy the large swimming pool seen in the panel. Supposedly, they only then realize that the pool could be repurposed as an actual neutrino detector. It is unclear what exactly, they had claimed to be building with the funding they somehow obtained. Given that they didn't know how a neutrino detector worked, it may be that the money was to find out how to build the detector, though such preliminary research would probably be far less expensive than the actual construction, and the budget wouldn't make sense. Through their own curiosity, they have then inadvertently ended up still somehow achieving their job!

It is unclear how large the pool in the comic really is. The {{w|Super-Kamiokande}} detector in Japan, one of the world’s largest and most well-known neutrino detectors, holds over 50,000 tons of water. This is approximately 20 times the water capacity of {{w|Olympic-size swimming pool}}s. The only statement made about the water capacity in the swimming pool is "huge", which is not a precise measurement of volume or mass{{Citation needed}}. The pool appears to be between 10 and 20 meters in diameter. While the surface of the pool seems to be at most half as large as that of an Olympic-sized pool, its depth could be approximately the same, since it seems to safely allow jumps from an approximately 1 m high platform. A regular pool of this appearance would be expected to hold less water than an Olympic-sized one, and certainly much less than would be required for an effective neutrino detector. Since the bottom of the pool is not visible, the physicists ''might'' just have built a pool with an appropriate volume by making it extremely deep. Assuming a diameter of 20 m and therefore a surface area of approximately 314 m², the pool would need to be approximately 159 m deep. Constructing such a pool would be even more expensive than building a neutrino detector{{acn}}, thanks to the large depth. It's more likely that the pool simply isn't circular with such a small diameter. The small size of the pool may not necessarily be a problem in the context of the cartoon: the final report to the funding agency would simply conclude "Would work, but we need a larger pool for the next one."

The title text elaborates on why the pool was suitable for a neutrino detector. In real life, these detectors must be heavily shielded from all other particle interactions that might drown out neutrino interactions. This generally requires them to be deep underground (like {{w|Deep Underground Neutrino Experiment|this}} and {{w|Sudbury Neutrino Observatory|this}} and {{w|Super-Kamiokande|this}}), so a surface-level pool would obviously be unsuitable for that purpose. Randall implies that the pool was built in a deep mine in order to prevent it from being noticed by the people responsible for funding the project, due to them having misused the funding money. This could fulfill the shielding requirement, but is a humorously excessive strategy for hiding a swimming pool from a small group of people.

==Transcript==
:[There is a large pool with a curved edge at the bottom of the panel, with a diving board and several stickfigures in and around it. Ponytail and Cueball are talking in the pool; two characters with relatively indistinct hair are in the water either side of them, passing a beachball between themselves; a Cueball has somersaulted off the diving board in a 'cannonball'-like jump; a Danish and a Ponytail with a drink are walking along the outside of the pool.]

: Ponytail in pool: How much trouble do you think we'll be in when they find out we used the grant money to throw a huge pool party instead?
: Cueball: We could argue that we '''''did''''' build a neutrino detector.
: Cueball: There's a lot of water here. A solar neutrino will probably interact with it at '''''some''''' point.
: Ponytail: ...Wait. Actually, if we got some photomultiplier tubes...

:[Caption below comic:]
:How the neutrino detector was invented

{{comic discussion}}<noinclude>
[[Category:Physics]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Danish]]
[[Category:Comics featuring Hairy]]
[[Category:Multiple Cueballs]]

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3249: Neutrino Project